Diet Tied to Better Breathing in COPD Patients

WEDNESDAY, May 21, 2014 (HealthDay News) -- People with certain
chronic lung diseases might breathe a bit easier when their diets
contain healthy foods like fruits and fish, a new study
suggests.

Researchers found that among nearly 2,200 adults with chronic
obstructive pulmonary disease (COPD), those who ate fish,
grapefruit, bananas and cheese tended to have better lung function
and fewer symptoms than their counterparts who did not eat those
foods.

COPD is an umbrella term for the progressive lung diseases
emphysema and chronic bronchitis. In the United States, about 15
million people have COPD, and the disease is the third leading
cause of death nationwide, according to the U.S. Centers for
Disease Control and Prevention. Smoking is the leading cause of
COPD.

It's not clear yet whether diet has direct effects on COPD
patients' lungs. The new study, reported at the American Thoracic
Society's annual meeting in San Diego, only shows an association
between certain foods and better lung function.

That doesn't prove cause-and-effect, said lead researcher
Corrine Hanson, who was scheduled to present the results on
Wednesday.

And no one is saying bananas are the magic bullet against COPD,
stressed Hanson, an assistant professor at the University of
Nebraska Medical Center in Omaha.

But COPD patients who eat fruit, fish and dairy products might
have a healthy, well-rounded diet, Hanson said. And it's
"plausible," she said, that foods that have antioxidant and
anti-inflammatory effects could benefit COPD patients' lungs.

That, in fact, is what some past research suggests, said Dr.
Carlos Camargo, a professor at Harvard Medical School who was not
involved in the new study.

In his own research, Camargo has found that people with diets
high in fruits, vegetables, fiber-rich grains and fish are less
likely to develop COPD compared to people who eat a lot of
processed foods, red meat and sweets.

"We think that diet as a whole is important," Camargo said. He added, though, that to really prove that a healthy diet improves lung function, you'd have to do a clinical trial -- where people with COPD would be randomly assigned to follow a particular eating plan or not.

"A trial like that is hard to do," Camargo noted. "But it can be done."

As an example, he cited the recent PREDIMED trial, which showed
that the classic Mediterranean diet can cut the odds of heart
attack and stroke in high-risk older adults.

"We should do something similar with COPD," Camargo said.

For the current study, Hanson's team used data from a larger
project that followed COPD patients over three years. At eight
different time points, the participants were asked whether they had
eaten grapefruit, bananas, fish or cheese over the past 24
hours.

In general, people who had eaten any of those foods showed
better lung function on standard tests, had a quicker walking pace,
and tended to have lower levels of certain inflammatory indicators
in the blood.

In some cases, the relationship was immediate, meaning people
who ate a certain food did better on certain tests the next day. In
other cases, the link was longer-term, meaning certain foods were
tied to better lung function over time.

Hanson said it's possible that some foods, such as fruits and
vegetables, have a short-term anti-inflammatory effect. But it's
more likely that the individual foods in this study are signs of a
higher-quality diet.

There's no good reason to suspect that eating a lot of cheese,
for example, would boost lung function. But, Hanson said, cheese
might be an indicator of people's intake of vitamin D, which, some
evidence suggests, might help COPD patients breathe a bit
easier.

"I think the take-away is that diet may be a modifiable factor for COPD patients," Hanson said. "When we think about diet and disease, we usually think about heart disease and diabetes. But people with lung disease should be thinking about diet, too."

Camargo agreed. "The lesson that's emerging is that foods like
fruits, vegetables and fish may be beneficial for lung health," he
said.

And if you're looking for a generally healthful way of eating,
Camargo and Hanson pointed to the Mediterranean diet. It's rich in
fruits and vegetables, whole grains, fish, beans and unsaturated
"good" fats from sources such as olive oil and nuts. It's also low
in processed foods, high-fat dairy and red meat.

Data and conclusions presented at meetings are typically
considered preliminary until published in a peer-reviewed medical
journal.

Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.